dom/xslt/base/txList.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef TRANSFRMX_LIST_H
   7 #define TRANSFRMX_LIST_H
   8
   9 #include "txCore.h"
  10
  11 class txListIterator;
  12
  13 /**
  14  * Represents an ordered list of Object pointers. Modeled after a Java 2 List.
  15 **/
  16 class txList : public txObject {
  17
  18 friend class txListIterator;
  19
  20 public:
  21
  22     /**
  23     * Creates an empty txList
  24     **/
  25     txList();
  26
  27     /**
  28      * txList destructor, object references will not be deleted.
  29     **/
  30     ~txList();
  31
  32     /**
  33      * Returns the number of items in this txList
  34     **/
  35     int32_t getLength();
  36
  37     /**
  38      * Returns true if there are no items in this txList
  39      */
  40     inline bool isEmpty()
  41     {
  42         return itemCount == 0;
  43     }
  44
  45     /**
  46      * Adds the given Object to the list
  47     **/
  48     nsresult add(void* objPtr);
  49
  50     /*
  51      * Removes all the objects from the list
  52      */
  53     void clear();
  54
  55 protected:
  56
  57     struct ListItem {
  58         ListItem* nextItem;
  59         ListItem* prevItem;
  60         void* objPtr;
  61     };
  62
  63     /**
  64      * Removes the given ListItem pointer from the list
  65     **/
  66     ListItem* remove(ListItem* sItem);
  67
  68 private:
  69       txList(const txList& aOther); // not implemented
  70
  71       ListItem* firstItem;
  72       ListItem* lastItem;
  73       int32_t itemCount;
  74
  75       nsresult insertAfter(void* objPtr, ListItem* sItem);
  76       nsresult insertBefore(void* objPtr, ListItem* sItem);
  77 };
  78
  79
  80
  81 /**
  82  * An Iterator for the txList Class
  83 **/
  84 class txListIterator {
  85
  86 public:
  87     /**
  88      * Creates a new txListIterator for the given txList
  89      * @param list, the txList to create an Iterator for
  90     **/
  91     explicit txListIterator(txList* list);
  92
  93     /**
  94      * Adds the Object pointer to the txList pointed to by this txListIterator.
  95      * The Object pointer is inserted as the next item in the txList
  96      * based on the current position within the txList
  97      * @param objPtr the Object pointer to add to the list
  98     **/
  99     nsresult addAfter(void* objPtr);
 100
 101     /**
 102      * Adds the Object pointer to the txList pointed to by this txListIterator.
 103      * The Object pointer is inserted as the previous item in the txList
 104      * based on the current position within the txList
 105      * @param objPtr the Object pointer to add to the list
 106     **/
 107     nsresult addBefore(void* objPtr);
 108
 109     /**
 110      * Returns true if a successful call to the next() method can be made
 111      * @return true if a successful call to the next() method can be made,
 112      * otherwise false
 113     **/
 114     bool  hasNext();
 115
 116     /**
 117      * Returns the next Object pointer from the list
 118     **/
 119     void* next();
 120
 121     /**
 122      * Returns the previous Object pointer from the list
 123     **/
 124     void* previous();
 125
 126     /**
 127      * Returns the current Object
 128     **/
 129     void* current();
 130
 131     /**
 132      * Removes the Object last returned by the next() or previous() methods;
 133      * @return the removed Object pointer
 134     **/
 135     void* remove();
 136
 137     /**
 138      * Resets the current location within the txList to the beginning of the txList
 139     **/
 140     void reset();
 141
 142     /**
 143      * Resets the current location within the txList to the end of the txList
 144     **/
 145     void resetToEnd();
 146
 147 private:
 148
 149    //-- points to the current list item
 150    txList::ListItem* currentItem;
 151
 152    //-- points to the list to iterator over
 153    txList* list;
 154
 155    //-- we've moved off the end of the list
 156    bool atEndOfList;
 157 };
 158
 159 typedef txList List;
 160
 161 #endif